Mitsubishi Repair: 98 eclipse rs (manual), vacuum hoses, airflow meter

Question
when i drive my car sometimes it lowers the rpm by its self   and the car shakes a little bit and after it makes a loud popping sound like a back fire and when im at a stop it idles at 2000 then at the next stop it ok, but then again it revs its self going up and down to 2000rpm at the next stop.

i tried a computer at autozone and it said it was the throttle body sensor, i changed it and no luck. i also changed the fuel filter and spark plugs and wires and it stop the shaking a little bit but it came back any ideas what it could be.

Answer
Cesar: You replaced the stark plugs, wires but did you also replace the distributor cap and rotor? Have you had the timing checked of late? The problem is this could be a lot of different things, I will give you some ideas right out of my repair manual. Oh one other thing, when you put the throttle body sensor in are you sure you did it right. In that did you have a repair manual to explain how it should be done. Some of those sensors are really touchy. Ok, next I would see if you might have a vacuum leak, check the mounting bolts/nuts at the throttle body and the air duct between the airflow meter and the throttle body for tightness; to make sure there is not air leaking at the gasket surface.Make sure there is not rips in the duct connections. Also make sure all the vacuum hoses are connected properly and in good shape. To find a vacuum leak is sometimes pretty hard might have to take the car to a shop and have them check for such a leak. How old is your air filter? Could be the EGR valve is leaking. So check those things and I hope one of them is your problem. God bless now: Linda